"She had wanted to get clean, but she was struggling with it," Lutfi, 38, said on the stand, and claimed that he took great lengths to help her kick the habit: Bringing drug-sniffing dogs to her home, and flushing a bag of white powder down the toilet.

Lutfi claims that he was hired by the "Toxic" singer as her manager for several months in 2007 and 2008, which was a memorable low point for Spears, who suffered a very public, frequently bizarre meltdown in the aftermath of her split from Kevin Federline and an ensuing custody battle.

He also claimed the real reason behind Spears' infamous head-shaving incident. "Britney was involved in a wicked child custody battle," he explained. "She told me someone had told her that they can scientifically test her hair for a history of drug use, so she shaved it off."

Spears offered Lutfi, a college dropout, a job as a manager soon after their meeting, he said. He eventually agreed on the condition that Spears would hire an agent and lawyer as well -- and that she would promise to quit drugs.

"She agreed," Lutfi said on the stands. "We even shook hands on it." One of his first actions as her manager was to bring the drug-sniffing dogs to her home in June 2007.

He also claimed the Grammy nominee had a drug relapse in September 2007, and called him the next month after spending the night in her car. He moved into her home, but insisted to jurors that the relationship was never romantic.

Lutfi is seeking 15 percent of Spears' earnings during the period that he worked for Spears; her attorneys argue that he never worked for her in an official capacity.

He's also claiming that the singer's mom, Lynne Spears, defamed him in her memoir Through the Storm, in which she wrote that Lutfi cut her off from her family and may even have drugged her food.

For her part, Britney Spears is in a much better place these days: With several successful comeback albums and tours behind her, she is now engaged to Jason Trawick, with live episodes of The X Factor to begin Nov. 1.